Synthesis of 5-dienyl pyrimidinones and tandem [1,5] shifts in [4+2] cycloadditions of 1,3-diazabuta-1,3-dienes with butadienylketene

Article abstract of DOI:10.1016/S0040-4039(98)01553-6

The reactions of 1-aryl-2-phenyl-4-methylthio-4-secondaryamino / 4-N- allyl-N-aryl amino-1,3-diazabuta-1,3-dienes 1 with butadienylketene leading to a mixture of 5-dienyl pyrimidinones 4 and 5-butenyl pyrimidinones 6 are reported. Tandem [1,5]H and [1,5]S